spandsp  0.0.6
telephony.h
1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * telephony.h - some very basic telephony definitions
5  *
6  * Written by Steve Underwood <steveu@coppice.org>
7  *
8  * Copyright (C) 2003 Steve Underwood
9  *
10  * All rights reserved.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU Lesser General Public License version 2.1,
14  * as published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 #if !defined(_SPANDSP_TELEPHONY_H_)
27 #define _SPANDSP_TELEPHONY_H_
28 
29 #if defined(_M_IX86) || defined(_M_X64)
30 #if defined(LIBSPANDSP_EXPORTS)
31 #define SPAN_DECLARE(type) __declspec(dllexport) type __stdcall
32 #define SPAN_DECLARE_NONSTD(type) __declspec(dllexport) type __cdecl
33 #define SPAN_DECLARE_DATA __declspec(dllexport)
34 #else
35 #define SPAN_DECLARE(type) __declspec(dllimport) type __stdcall
36 #define SPAN_DECLARE_NONSTD(type) __declspec(dllimport) type __cdecl
37 #define SPAN_DECLARE_DATA __declspec(dllimport)
38 #endif
39 #elif defined(SPANDSP_USE_EXPORT_CAPABILITY) && (defined(__GNUC__) || defined(__SUNCC__))
40 #define SPAN_DECLARE(type) __attribute__((visibility("default"))) type
41 #define SPAN_DECLARE_NONSTD(type) __attribute__((visibility("default"))) type
42 #define SPAN_DECLARE_DATA __attribute__((visibility("default")))
43 #else
44 #define SPAN_DECLARE(type) /**/ type
45 #define SPAN_DECLARE_NONSTD(type) /**/ type
46 #define SPAN_DECLARE_DATA /**/
47 #endif
48 
49 #define SAMPLE_RATE 8000
50 
51 /* This is based on A-law, but u-law is only 0.03dB different */
52 #define DBM0_MAX_POWER (3.14f + 3.02f)
53 #define DBM0_MAX_SINE_POWER (3.14f)
54 /* This is based on the ITU definition of dbOv in G.100.1 */
55 #define DBOV_MAX_POWER (0.0f)
56 #define DBOV_MAX_SINE_POWER (-3.02f)
57 
58 /*! \brief A handler for pure receive. The buffer cannot be altered. */
59 typedef int (span_rx_handler_t)(void *s, const int16_t amp[], int len);
60 
61 /*! \brief A handler for receive, where the buffer can be altered. */
62 typedef int (span_mod_handler_t)(void *s, int16_t amp[], int len);
63 
64 /*! \brief A handler for missing receive data fill-in. */
65 typedef int (span_rx_fillin_handler_t)(void *s, int len);
66 
67 /*! \brief A handler for transmit, where the buffer will be filled. */
68 typedef int (span_tx_handler_t)(void *s, int16_t amp[], int max_len);
69 
70 #define ms_to_samples(t) ((t)*(SAMPLE_RATE/1000))
71 #define us_to_samples(t) ((t)/(1000000/SAMPLE_RATE))
72 
73 #if !defined(FALSE)
74 #define FALSE 0
75 #endif
76 #if !defined(TRUE)
77 #define TRUE (!FALSE)
78 #endif
79 
80 /* Fixed point constant macros */
81 #define FP_Q_9_7(x) ((int16_t) (128.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
82 #define FP_Q_8_8(x) ((int16_t) (256.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
83 #define FP_Q_7_9(x) ((int16_t) (512.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
84 #define FP_Q_6_10(x) ((int16_t) (1024.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
85 #define FP_Q_5_11(x) ((int16_t) (2048.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
86 #define FP_Q_4_12(x) ((int16_t) (4096.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
87 #define FP_Q_3_13(x) ((int16_t) (8192.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
88 #define FP_Q_2_14(x) ((int16_t) (16384.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
89 #define FP_Q_1_15(x) ((int16_t) (32768.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
90 
91 #define FP_Q_9_23(x) ((int32_t) (65536.0*128.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
92 #define FP_Q_8_24(x) ((int32_t) (65536.0*256.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
93 #define FP_Q_7_25(x) ((int32_t) (65536.0*512.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
94 #define FP_Q_6_26(x) ((int32_t) (65536.0*1024.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
95 #define FP_Q_5_27(x) ((int32_t) (65536.0*2048.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
96 #define FP_Q_4_28(x) ((int32_t) (65536.0*4096.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
97 #define FP_Q_3_29(x) ((int32_t) (65536.0*8192.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
98 #define FP_Q_2_30(x) ((int32_t) (65536.0*16384.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
99 #define FP_Q_1_31(x) ((int32_t) (65536.0*32768.0*x + ((x >= 0.0) ? 0.5 : -0.5)))
100 
101 #if defined(__cplusplus)
102 /* C++ doesn't seem to have sane rounding functions/macros yet */
103 #if !defined(WIN32)
104 #define lrint(x) ((long int) (x))
105 #define lrintf(x) ((long int) (x))
106 #endif
107 #endif
108 
109 #endif
110 /*- End of file ------------------------------------------------------------*/